Sydney: A fourth search vessel equipped with a sophisticated underwater drone is set to join the search for missing Malaysia Airlines Flight MH370, the Australian search coordinator said on Wednesday.

Months of searches have failed to turn up any trace of the Boeing 777 aircraft, which disappeared on March 8, carrying 239 passengers and crew shortly after taking off from the Malaysian capital of Kuala Lumpur, bound for Beijing.

The current phase of the search is focusing on a rugged and previously unmapped 60,000-sq-km (23,000- sq-mile) patch of sea floor some 1,600 km (1,000 miles) west of the Australian city of Perth.

Dutch engineering firm Fugro has deployed three vessels to map and then search the sea floor in the area.

The new search vessel, Fugro Supporter, is equipped with a Kongsberg HUGIN 4500 autonomous underwater vehicle (AUV), which is pre-programmed with an area to search and then released, rather than tethered to a ship via a cable.

"The AUV will be used to scan those portions of the search area that cannot be searched effectively by the equipment on the other search vessels," Australia`s Joint Agency Coordination Centre (JACC) said in a statement.

More than 14,000 sq km of sea floor has been searched, JACC said, and the search of the current area could be completed as early as May, provided there are no delays.

Fugro Supporter is expected to arrive in the search area in late January.

On July 17, the same airline`s Flight MH17, also a Boeing 777, was shot down over Ukraine, killing all 298 people on board.

Another Malaysian-affiliated aircraft, an Indonesia AirAsia Airbus A320-200, crashed on a flight from Indonesia to Singapore on Dec. 28 with the loss of all 162 people on board. Its wreckage has been found and its flight recorders are being examined.